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Note: Individual engines’ SFC(Specific Fuel Consumption) & Individual aircrafts’ standard Air-Air payload weight, based TWR cannot be determined due to unavaliability of SFC data for Older Engines. Even in the case of some Newer Engines, SFC data is not avaliable.

It’s unclear whether the 35,000lbf thrust for F119(F-22’s engine) is the actual thrust output. It’s known that a Flat nozzle reduces the thrust of an engine anywhere between 14% to 17%. Further it’s mentioned in official sources that the engine is of 35,000lbf Class, meaning the 35,000lbf number is not the precise engine output, and the actual output is somewhere around it. Generally, in official publications, when an engine output is mentioned in the form of ‘Class’, the actual output is less than the number given. It could be that the engine can very well produce 35,000lbf with normal nozzles during testing, but the mating of Flat Nozzle(instead of the normal Round one) reduces the thrust, hence the ‘Class’ designation for the engine’s output. For an engine thrust decrease of 14%, F-22’s TWR would drop down to 1.18. Given the fact that the F-35’s engine, which is a derivative of the F-22’s engine, but newer & bigger than the F119 engine, has a thrust of 39,900lbf with round nozzles, it’s likely the 35,000lbf fig for F119 is also for round nozzles. F-35’s engine F-135, just recently got its thrust upgraded to 43,000lbf. To further illustrate the data sheet’s/brochure’s failure of mentioning the loss of thrust for Flat Nozzles, the F-117’s F404-GE-F1D2 engine which is a non-afterburning, flat nozzle engine[1], is mentioned as having the same 10,600lbf[2] non-afterburning thrust as the F404-GE-400 engine[3]. F404-GE-F1D2 is basically a non-afterburning F404-GE-400 engine with a flat nozzle.[4]

Data from Official Company & Military sites

Weight in lb, and Thrust in lbf.

3505 kg = 7727 lb

Not all of them are Fighter Planes.

Some of the Fighters’ data couldn’t be obtained, and hence could not be included in the below list.

# Data from Official Company & Military sites, Aerospaceweb.org, Airwar.ru, Globalsecurity.org, Fas.org, Warfare.ru, Wikipedia.org & its References, and Other Sources.
# Weight in lb, and Thrust in lbf.
# 3505 kg = 7727 lb
# Not all of them are Fighter Planes.
# Some of the Fighters’ data couldn’t be obtained, and hence could not be included in the above list.
# Individual engines’ SFC(Specific Fuel Consumption) & Individual aircrafts’ standard Air-Air payload weight, based TWR cannot be determined due to unavaliability of SFC data for Older Engines. Even in the case of some Newer Engines, SFC data is not avaliable.
# It’s unclear whether the 35,000lbf thrust for F119(F-22’s engine) is the actual thrust output. It’s known that a Flat nozzle reduces the thrust of an engine anywhere between 14% to 17%. Further it’s mentioned in official sources that the engine is of 35,000lbf Class, meaning the 35,000lbf number is not the precise engine output, and the actual output is somewhere around it. Generally, in official publications, when an engine output is mentioned in the form of ‘Class’, the actual output is less than the number given. It could be that the engine can very well produce 35,000lbf with normal nozzles during testing, but the mating of Flat Nozzle(instead of the normal Round one) reduces the thrust, hence the ‘Class’ designation for the engine’s output. For an engine thrust decrease of 14%, F-22’s TWR would drop down to 1.18. Given the fact that the F-35’s engine, which is a derivative of the F-22’s engine, but newer & bigger than the F119 engine, has a thrust of 39,900lbf with round nozzles, it’s likely the 35,000lbf fig for F119 is also for round nozzles. F-35’s engine F-135, just recently got its thrust upgraded to 43,000lbf. To further illustrate the data sheet’s/brochure’s failure of mentioning the loss of thrust for Flat Nozzles, the F-117’s F404-GE-F1D2 engine which is a non-afterburning, flat nozzle engine[1], is mentioned as having the same 10,600lbf[2] non-afterburning thrust as the F404-GE-400 engine[3]. F404-GE-F1D2 is basically a non-afterburning F404-GE-400 engine with a flat nozzle.[4]

* Klimov States that Thrust as “Take-off emergency mode”
** The conditions for 21,829lbf Emergency Thrust are limited to 3 Minutes and Altitude less than 4000m.
*** Empty weight + 7727 lb exceeds max takeoff weight. Except Mig-19 all other less MTOW(Maximum Take-Off Weight) fighter planes are omitted.
**** Official tejas.gov.in Website claims the Thrust of F404-GE-IN20 as 20,200lbf which contradicts with the manufacturers’ claim of 19,100lbf. Most likely the 20,200lbf figure is for Emergency Thrust. Also Tejas has gotten heavier by about 60kgs thus bringing its TWR to 0.86 from 0.87 .

If the F-35 had only one engine, would the thrust be half, or more than half of the value given in the table? I have heard that the Pentagon wanted just one engine, but was overruled by Congress in budget considerations.

What is the rationale for 3.505 ton weight.This table is meaning less.TWR is calculated as empty weight+half fuel capacit in litres*.803 specific weight for fuel(for weight in KG)+ couple of air to air missiles.
This is the combination with which fighters go into dog fight.So the basic criteria for calculation is wrong

Congratulations for a rather tedious labour undertaken. It provides a start, statistical basis for evaluation, discussion and eventually a priority frame setting. One point I miss though (as a layman on this subject, sorry). Are all things equal when we bring in the performance dynamics scale of each fighter under different, fluctuating atmospheric conditions? Do the TWR data remain value-free or say “value-neutrally stable” whether the dogfight is taking place in the thin Himalayan air or over a tropical, moisture dense, windy forest near Bangladesh or elsewhere?. Will not the metallic quality of the fighter say something or has it no significance for TWR at all? I understand Russians are experts in titanium alloys. Possibly a titanium-aluminium plus plus combination perhaps?

Secondly, the stealth technology value seems to have been overlooked in this fighting potential issue. Why should stealth tech not applied to a bomber-fighter category and not for bombers alone? It may not be academically appropriate if I bring in an analogy from a summer sunny day event that I watched with amusement. Sitting under a tree shade on a park bench here in Vienna, I threw repeatedly very small pieces of bread crumbs for 2 types of birds to pick – one was sparrow and the other dove. The doves around, almost a troop battalion size, outnumbered the few sparrows perched on tree branches, but the doves were stably footed on ground. The moment I threw the sparrows were superbly“fast” in picking these crumbs with a fly-dive from a longer distance, infuriating the frustrated doves moving only as fast as they could, but alas with nil bounty. It was a 95% sparrow win.

Now applying this to fighters, India’s LCA Tejas can perform exceedingly well and better, if stealth technology is injected into its production line, plus the engine and sub-technologies improved substantially to fly past with enhanced mobility and manoeuvrability. From the Republic Day pics the Tejas looks quite slim. A titanium alloy or other titanium compound metal combination would presumably make it harder and faster, and with stealth capability, it could principally perform “smart” wonders like the sparrow. I would much appreciate an expert’s feedback on this.

Just some added info. The F-119 engines were naver tested with round nozzles.

The PW5000 (developmental designation for what would become the F119) ran with various iterations of square nozzles, but no round ones. Any performance numbers released are from a production configured engine with square nozzles.

(edited)
Just some added info. The F-119 engines were never tested with round nozzles.

The PW5000 (developmental designation for what would become the F119) ran with various iterations of square nozzles, but no round ones. Any performance numbers released are from a production configured engine with square nozzles.

The U.S. govt. has ended F-22 Raptor production. It was too expensive and had oxygen system problems leading to pilot death(s). It was also considered not an easy aircraft to manoeuvre with. The less expensive and more versatile F-35 (a further development of F-22) is what merits focus now. F-22’s field performance record is meagre too. One complete fleet is based in Japan and was probably used in the recent reconnaissance operations vis-a-vis China. But field performance data are not accessible. They were also not on dogfight combat missions.

The engine nozzle architecture (whether square or round) evaluation is meaningful only in conjunction with the total aerodynamic performance of the aircraft. The dead weight performance in Lockheed Martin’s or partner Boeing’s aerodynamic chambers should have been the decider for a decision to go in for either square or rounded nozzles. Here too the sub-technologies’ system performance data are not available. Presumably no company will release those in view of close watch from competitors. Indications so far are that F-35’s TWR values must have been high and impressive. A piece costs over $ 270 mil. Raptor’s initial price of $370/piece was too high even for the USAF’s domestic demand.

In addition, F-22 Raptor’s additional capabilities have been cited: ground attack, electronic warfare, and signals intelligence roles. These are areas where India sadly needs technology boost. The key lies in avionics. F22 Raptor used a CIP (Common Integrated Processor) from Raytheon with 10.5 billion instructions/sec. using sensor fusion (multiple data from different systems fused into common view for the pilot to operate in an easy “un-overwhelmed” manner. It had 1.7 million lines of code for radar data processing, had WiFi access point, could transmit data at 548 megabits/sec. and receive at gigabit speed. This is supposedly faster than the Link 16 system used elsewhere. As mentioned before (in one of my previous communications to DFI), unless India develops vertically integrated, advanced, microelectronic foundry lines from crystal growth to advanced chip production, it will never have a sustainable, reliable, defence high-quality production base, be it IAF, Navy or Army. When I confronted an ISRO chairman long years past on this deficit, he readily conceded that we neglected this area.